Manufacturers in home page: problems

Hi,
I've seen different topics much or less about the same issue, still without an answer.
The issue regards the manufacturers module at the bottom of the homepage.
If I select as datasource the Joomla categories, the links will not work. At the "Images & links" tab I've tried to set different links but still it's not working.
If I select a different data source, for example Virtuemart categories, it will pop up a strange error, which I attach hereby.
So, I am blocked.
I need the people to be able to click on those images and to go on the category page (specifically, in my case the virtuemart categories): the fact that the visitors click on those manufacturers image and nothing happens except but topping up to the same homepage (as it is in your demo now) it's useless.
Please give us assistance, it will help many people.
Thank you a lot

If needed: this is my url: http://bookletnews.it/ . Attached the error.

Did you try to create a menu item with the same category as modules data source. This is a common joomla limitation as without a menu item none of the links will work. This goes for joomla articles, k2 articles and so on.

For an example.

Lets say we have following joomla article categories.
News/
News/Sports
News/Finance

Now creating a direct link to Sports , any links belong to Sports articles will work and display fine, any links belong to Finance or News categories will not work.

Create a direct link to News and all News links and links under Sports and Finance will work.

For your test if your data source is Virtuemart > Manufacturers then create a menu item for Manufacturers.
If its a K2 category then create a menu item to this category. Let me know how you get on...

Hi NormanUK,

thanks for your answer.
Actually, the data source I am trying to use are not Virtuemart manufacturers, but Virtuemart categories, and yes, they are already published on the main menu as menu items.
The point is that when I try to select them as data source in the module configuration, an error message pops-up (that one I attached in my previous post).

Could you figure out what's causing the problem and how to solve it?

Thank you again

I am sorry file you have attached is not visible. Perhaps send me an admin access details and I can check it out. You can send the details to my email normanuk[at]live.co.uk or via a private message in here.

See you around...

Dear Norman, once again thanks for the fast answer.
I've tried to attach the screenshot once more, somehow it's not taking it I see. By the way I've sent you an email with the credentials.
Thanks a lot.

Looking into it right now, will keep you posted.